Flowing Fix: How to make a bootable Mountain Lion install drive and use the media once created

For various reason you might want to have a copy of the Mac OS software, here is how to do it and use the media that you created

This can be done using two different media formats:

• USB flash drive or other removable media
• Dual-layer DVD (note that single-layer disk is too small for Mountain Lion, but was okay for Lion)

The instructions for each one of the media types is as follows (common instruction):

1. Download Mountain Lion from the Mac App Store

(NOTE: if you have already downloaded and installed Mountain Lion on your Mac you will have to re-download the software, using the  "Option" button and click on the app in the Mac App store.  Follow the detailed information at this website: http://macs.about.com/od/usingyourmac/qt/How-To-Re-Download-Apps-From-The-Mac-App-Store.htm )

USB flash drive or other removable media option:

(Via: http://www.macworld.com/article/1167857/how_to_make_a_bootable_mountain_lion_install_drive.html )

Using Disk Utility You’ll find this utility in your Utilities folder (in /Applications/Utilities). Here are the steps for using it to create your installer drive:

.

1. Once you’ve purchased Mountain Lion, find the installer on your Mac. It’s called Install OS X Mountain Lion.app and it should have been downloaded to your main Applications folder (/Applications).
2. Right-click (or Control+click) the installer, and choose Show Package Contents from the resulting contextual menu.
3. In the folder that appears, open Contents, then open Shared Support; you’ll see a disk image file called InstallESD.dmg.
4. Launch Disk Utility.
5. Drag the InstallESD.dmg disk image into the bottom (empty area) of Disk Utility’s sidebar (on the left).
6. In Disk Utility, select InstallESD.dmg in the sidebar, and then click the Open button in the toolbar to mount the disk image’s volume in the Finder. The mounted volume is called Mac OS X Install ESD, and it also appears below InstallESD.dmg in Disk Utility.
7. Select Mac OS X Install ESD in Disk Utility’s sidebar, then click the Restore button in the main part of the window.
8. Drag the Mac OS X Install ESD icon into the Source field on the right (if it isn’t already there).
9. Connect to your Mac the properly formatted hard drive or flash drive you want to use for your bootable Mountain Lion installer.
10. In Disk Utility, find this destination drive in the left-hand sidebar and then drag it into the Destination field on the right. (If the destination drive has multiple partitions, just drag the partition you want to use as your bootable installer volume.) Warning: The next step will erase the destination drive or partition, so make sure it doesn’t contain any valuable data.
11. Click Restore, and then Erase in the dialog box that appears; if prompted, enter an admin-level username and password.

Dual-layer DVD option:

(Via : http://macs.about.com/od/macoperatingsystems/ss/Create-Bootable-Copies-Of-The-Os-X-Mountain-Lion-Installer_3.htm )

With Mountain Lion's InstallESD.dmg file mentioned above in step 3, copy the dmg to your Desktop. Now, we're ready to burn a bootable DVD of the installer.

1. Insert a blank DVD into your Mac's optical drive.
2. If a notice asks you what to do with the blank DVD, click the Ignore button. If your Mac is set up to automatically launch a DVD-related application when you insert a DVD, quit that application.


3. Launch Disk Utility, located at /Applications/Utilities.


4. Click the Burn icon, located in the top right corner of the Disk Utility window.


5. Select the InstallESD.dmg file you copied to the Desktop in an earlier step.


6. Click the Burn button.


7. Place a blank DVD into your Mac's optical drive and click the Burn button again.


8. A bootable DVD containing OS X Mountain Lion will be created.


9. When the burn process is complete, eject the DVD, add a label, and store the DVD in a safe location.

To use the media to do a fresh install of Mountain Lion follow these steps:

1.  Back up your Mac, e.g., TimeMachine backup, and disconnect backup from computer, and put the backup in a safe place.

2.  Insert the media with the Mountain Lion copy into your Mac.

3.  Shut down your Mac.

4.  When starting the Mac, press and hold down the appropriate key:

4a)  for booting from DVD drive: press and hold down "C" button on Mac keyboard just after pressing the power. Once you notice the Mac is using the media, you can release the "C" key

or

4b) for booting from USB port: press and hold down "Option" button on Mac keyboard just after pressing the power. Once you notice the Mac is using the media, you can release the "Option" key

(If you need more detailed guides to do this media installation refer to  http://macs.about.com/od/macoperatingsystems/ss/Create-Bootable-Copies-Of-The-Os-X-Mountain-Lion-Installer.htm )